In recent years, the demands for photographic consumption goods have been kept increased in the market by such a level as high as about 10% per annum. When a photographer desires to keep his memories on photographic pictures, he expects the pictures should be finished in the finest quality whenever he takes pictures at any time and places, so that his shutter chances for taking pictures of subjects are increased.
The chances of taking pictures on the color photographic light sensitive materials having a high speed of not slower than ISO 300 are steadily increased, as the image qualities are improved year by year.
Such high speed color photographic light-sensitive materials are very often used for taking pictures not only in open daylight, but also indoors. In the indoor photography, there normally uses an artificial light source such as an electronic flash --so-called a strobe--, an incandescent tungsten lamp, a fluorescent lamp, and a mercury lamp. Among the indoor photography, for example, in those at a wedding hall, a stage, a show window, an indoor athletic facility, and a night scene, there are many instances where no electronic flash can be used, but one of the various artificial light sources such as an incandescent tungsten lamp, a fluorescent lamp and a mercury lamp are used.
As generally compared to color reversal photographic light-sensitive materials, the color negative photographic light-sensitive materials are relatively wider in latitude, so that they are not particularly necessary to carry out the color correction even when using any one of various light sources and, in addition, they have a further excellent characteristics that a color reproduction can be corrected when carrying out a printing operation.
However, in the case of taking picture on a color negative photographic light-sensitive material by making an exposure to a light source having a color temperature different from those of the so-called daylight colors and then correcting a color reproduction when carrying out a printing operation, the quality of the finished print is often deteriorated and, particularly, the graininess thereof is often conspicuously deteriorated,.as compared to those of the color printed pictures made by making an exposure to a daylight.
Therefore, for taking pictures on a high speed color negative photographic light-sensitive material by making an exposure to any one of various light sources each having different color temperatures, it has been demanded that the image qualities and, particularly, the graininess, can be so obtained as to be equivalent to those obtained by making an exposure to the daylight.
Heretofore, there have been many attempts to improve the graininess. However, those attempts have still not always been effective to solve the problems posed to the high speed color negative photographic light-sensitive materials.
For example, Japanese Patent Publication Open to Public Inspection --hereinafter referred to as Japanese Patent O.P.I. Publication--No. 62-91945/1987 discloses a technique for improving the graininess in an underexposed area, in which a light-sensitive unit is comprised of three layers; namely, a low speed emulsion layer, a medium speed emulsion layer and a high speed emulsion layer; and the maximum color density of the high speed emulsion layer is set to be not higher than 0.3. In this technique, it could be proved that the graininess around a minimum density+0.2 and the image quality in the underexposed areas were both improved though, the graininess in the areas exposed to various light sources each having different color temperatures were considerably deteriorated as compared to those exposed to the daylight.
There has been a known method in which the graininess can be improved by coating the amount of the silver halide grains more than that used in the conventional type of films. When applying this method to the above-mentioned high speed light-sensitive materials, there are many instances where the graininess thereof is seriously deteriorated in the course of naturally aging the light-sensitive materials and, in addition, it can hardly be said that this method is positively applicable to the high speed light sensitive materials, from the viewpoints of preventing image qualities such as a resolving power from being lowered, and saving the production cost.
On the other hand, as a means for improving an image quality, there have been the known techniques in which a photographically useful reagent such as a development inhibitor is released silver-imagewise at the same time when forming a silver image. In the field of color photographic light-sensitive materials, these techniques include, typically, a technique in which a DIR compound is added. From the viewpoints of emphasizing an interimage effect, --IIE--, and improving color reproduction, graininess and image sharpness, the technique having been most popularly used is that for adding a diffusible DIR compound which releases diffusible development inhibitor. However, while the use of the compound is inevitably useful for obtaining a high image quality in an ordinary photographing operation, the use thereof has the defects that, when taking picture under a light source having a color temperature different from those of daylight, the interimage effect is unbalanced to deteriorate the gradation and, therefore, the color balance between the highlight portions and the shadow portions are off even if a color correction is carried out when the image is printed, so that a satisfactory color reproduction cannot be obtained. In addition to the above, the sensitive speed is sharply lowered and, therefore, this technique is not effective as a means for improving the graininess of such a high speed color photographic light-sensitive material, though the graininess itself may be improved.
As described above, the problem remaining unsolved in the conventional techniques is that, when taking picture on a high speed color negative light-sensitive material by making an exposure to one of various light sources having a color temperature different from those of the daylight, any graininess cannot be obtained as excellent as those obtained in daylight conditions. The invention is to solve the above-mentioned problems under the various restrictive conditions for designing a high speed color negative photographic light-sensitive material, such as an amount of silver contained.sup.. a layer thickness.sup.. a silver halide grain size.sup.. an amount of couplers.sup.. an amount of DIR compounds contained.sup.. etc.